LPG 액상분사식 인젝터 분사팁의 아이싱 발생 특성 연구

The use of clean gaseous fuel for the purpose of high efficiency and low emission in automotive engines has tendency of increase in order to meet the reinforcing emission regulations and to efficiently utilize limited natural resources. Since the liquid phase LPG injection (LPLI) system has a very strong potential to accomplish the higher power, higher efficiency, and lower emission characteristics than the mixer type fuel system, automotive companies developed and commercialized it. However, when a liquid LPG fuel is injected into the inlet duct of an engine, a large quantity of heat is extracted due to evaporation of fuel. This leads to freezing of the moisture in the air around the outlet of a nozzle, which is called icing phenomenon. It may cause damage to the outlet nozzle of an injector or inlet valve seat. This research examines the characteristics of icing phenomenon and also aimed to improve it through the use of anti-icing bushing at the fuel injection tip. The result showed that the icing phenomenon and process were mainly affected by humidity and temperature of inlet air in the inlet duct. Also, it was observed that the icing phenomenon improved by using aluminum bushing whose end matches the end of fuel injection tip in length.